Behind the VFX of 'The Christmas Chronicles 2'

Source: Befores and Afters

Weta Digital explains how they created elves, Jack-a-lotes, Santa's flying sleigh, snowy environment and… a Yule Cat.

Working with director Chris Columbus, Weta Digital led an extensive effort to bring the world of Netflix’s The Christmas Chronicles 2 to life. The film tells the story of how once-elf-now-human character Belsnickel (Julian Dennison) threatens to cancel Christmas, and how Santa Claus (Kurt Russell) and Mrs. Claus (Goldie Hawn) and their helpful elves and new-found human friends look to save the day.

Weta Digital’s tasks included significant CG character animation, world-building and a variety of magical effects. Here, Martin Hill (production visual effects supervisor), Phil Leonhardt (additional visual effects supervisor) and Thrain Shadbolt (additional visual effects supervisor) and Nick Stein (animation supervisor) break down some of the individual VFX challenges, and share befores and afters images to showcase the work.

Building Belsnickel and the elves

Martin Hill: We got the models from the first film. A lot of characters from the first film are in the second; we stripped them back and overall re-styled them. They’re a little bit bigger from the first film, here. Then, we re-did their costumes and worked really closely with Pierre-Yves Gayraud, the costume designer, just to get his take on how the costumes would flow and then made them up in Marvelous Designer.

Then our lookdev supervisors, Olivier Beierlein and Jasmine Wong, went really deep into all these kinds of Nordic-like jumpers and Christmas patterns and worked out a really elegant way to make the woollen knitted jumper-type material have all its pilling and little fly-aways, with some really elegant ways to swap out all the materials and colors.

Phil Leonhardt: Our textures and shaders team did come out in the end knowing how to knit a jumper in all sorts of different patterns, which was quite amazing.

Martin Hill: Yeah, our crew gear for the show is amazing!

Phil Leonhardt: Knitted jumpers for everyone…

Nick Stein: In terms of animation, very early on we did a lot of tests. We jumped on the mocap stage because we got a brief pretty early on that they wanted the elves to be more real, grounded, more weighted. So straightaway you think you’re going to get that lovely nuance in mocap. We jumped onto the stage, did some tests, and you could tell that the scale difference between a human performer and an elf didn’t quite work. We did some tricks to speed it up, make it more bouncy, add a little bit of squash and stretch. We tried keyframing as well and we really found that each shot needed its own kind of way forward.

I would say in the end we pretty much used a blend of every trick for every shot. We would always start with a base of mocap, particularly for the more dramatic acting sequences. But as soon as you’d have to break that physicality and the physics of the world, then you’d go to keyframe and you’re blending in all these smear frames and things like that.

Martin Hill: For Belsnickel in particular, when Julian was cast, it was a real help for us because he’s so charismatic and he has such great expressions and he really hits comedy poses. So one of the main things when we were designing Belsnickel elf was, ‘Okay, we need to sit in the world of elves, but also we need to imbue him with all of Julian’s personality traits.’ So it was a matter of taking his features and elf-ifying them.

We were lucky enough to do some re-shoots here in New Zealand, and by then we had all the designs and could show Julian. He was like, ‘Man, that’s freaky, it looks like me.’ Which was just really gratifying to hear. And then it was also about, ‘How do we get some of the fun and cartooniness back into the elves?’ It was about getting the extreme shapes, being able to roll their eyes in opposite directions when they fall down the stairs and really being able to hit some un-physical poses as well.

Nick Stein: For Belsnickel and all the elves, we didn’t actually do facial capture, but we did have our actors on the mocap stage when they’re doing their body performances. Here we would film their faces. They didn’t in this particular instance have the full headsets that we usually use, although we did build upon the muscle-based systems we had created for Alita: Battle Angel and Planet of the Apes. But here we needed to push forward on making sure that these characters could still kind of hit these cartoony shapes.

Thrain Shadbolt: In terms of the lighting of Belsnickel and the elves, we’d start with a very technical setup where we could be sure we were matching what was on the set. But then that wouldn’t necessarily always achieve the kind of look on the faces of the elves that the director was going for. And so we’d often come in and just have to beauty light the elves, particularly Belsnickel and some of the other hero elves in such a way that they had more kind of sympathetic, maybe slightly more cartoony, feel than what pure realism would dictate. We’d particularly lift shadows around the faces and so on, giving them a little bit of a softer look.

Phil Leonhardt: I think another thing that we also realized with the elves in particular is that on the larger scale wider shots, is how many you need to make them actually ‘present’ in the shot, because they are fairly small creatures. So if you put a small elf on the ground here and maybe one on the stone ledge over there and you have these wide shots with the actors, you very easily miss them. So we very quickly realized that we had to put some on the balustrades, on the balconies up the top there to kind of really fill the frame and compose it all out. I think that’s why we ended up with a substantial amount of elves and variants, because if you have all the hundreds of elves in a scene, you want to make sure that each one of them is unique so they don’t all look like twins.

Thrain Shadbolt: In the finale, where we literally had hundreds of elves, we did have someone whose job it was just to check all the shots and make sure we didn’t have too many twins or triplets and make sure that the color scheme on the elf costumes was working in such a way that we had all that variation out there and also had all those Christmas-y colours.

Nick Stein: One particular sequence we did with the elves we called the ‘Rambo run’, where it was just this chaotic scene of Jack (Jahzir Bruno) running through with a Nerf gun shooting off elves and bombs going off. When we first did that, we did a pass and we got everything we wanted to get in there. But then we took a step back and it was just chaos everywhere so we really wanted to find a way to drive the audience through the shot. We came up with this storyline of these two jousters, and the animators just had fun playing with that.

Thrain Shadbolt: There’s also a moment towards the end of the film—spoiler alert—where Belsnickel transforms from his human self back down to his elven self. We have a nice little sequence of shots that I think works really well and it’s quite funny during that transformation; the change from Julian into his CG form.

Shooting scenes

Martin Hill: It was super-important to me when I first talked to Chris that we didn’t go and shoot plates with actors and then later on decide, ‘Okay. Where are we going to put the elves?’ We wanted to commit to what the actions were going to be and get as much interaction between physical objects on the stage and what the elves and the CG characters were doing. A lot of that was really small little things. Like when Hugg jumps on the table, we’ve got a bit of mono attached to the table and you get a little bit of pull with the right timing to give the table a nudge. And that wouldn’t be a terribly difficult thing to do in CG, or maybe you wouldn’t miss it if the table didn’t knock a little bit when the elf jumped on, but it just embeds them a little bit more.

When Jojo and Hugg are making hot chocolate and pouring it out, we had puppeteers physically pour from a ladle the hot chocolate into a cup. We can do physically accurate hot chocolate sims, but it really helps the actors see what’s going on and they know what they’re looking at, and it also just means that the DOP’s seeing more of what’s going to happen in the final shot and the director’s going to see more.

I think my favorite one in terms of interaction was the end of the arctic wilderness chase where the Yule Cat Jola appears behind Julian and our previs had him give him this big lick on his face. We had a big maquette of Jola’s head and got a couple of puppeteers behind that and really gave Julian a big physical shove that he reacted to and almost stumbled in the snow a little bit. And then we attached a big wet sponge to it for the tongue as well, so they twisted it around to give him a lick in the face, which he genuinely looks quite appalled at the sight of it. If he was only miming it, it wouldn’t quite work.

Then, Speck, one of the elves, jumps off Jola and does a little dance on Julian’s shoulder. So we had another little puppet with two little legs that was just nudging around his epaulettes on his shoulder, it really help him to put everything together.

Thrain Shadbolt: Any time you can mix techniques together in one shot, I think it makes it that much harder for people to spot how things are done. I think that’s why there’s a lot of value in bringing stuff in that’s not just CG to these kinds of shots.

Phil Leonhardt: For that particular shot with the little elf on Belsnickel’s shoulder, if you can master that convincingly that is such a rewarding outcome because you know you put all that effort and all that planning into it. They’re generally the hardest shots to do, I think, because not only do we have to have a hell of a paint-out of all the puppeteering, all the props, and have to reconstruct parts of the face and parts of the shoulder and whatnot, you also have to get incredibly accurate match moves.

You have to get your camera set up working perfectly and then it passes on to the animators and they’re just really intricately trying to mimic every step, yet having to know that it still has to be within the character of the elf at the same time. So there’s just so many things going in there, and then after months of work on that you see the final result and you go, ‘Wow, this just worked incredibly, amazing.’ It’s just such a rewarding thing to do.

Filling out the world of Christmas Chronicles 2

Martin Hill: Originally, we were supposed to shoot some of the outdoor scenes for the arctic in Brandywine just outside of Vancouver. We found the sort of perfect place and then we waited for snow.

Nick Stein: And waited.

Martin Hill: And waited. It ultimately became our baseline environment but then we added a lot of magic on top, because it needed to be a fantastical place. This was contrasted with the Antarctic wilderness, where we took some of those elements and made them more bleak.

Phil Leonhardt: We found looking at the Antarctic versus the arctic that, first of all, you don’t have any trees and you also have quite a lot of ragged, spiky, nasty looking mountain ranges that you can feed in and make it kind of a hostile place—only Belsnickel would build his cave down there. Nobody else really wants to go down there.

Martin Hill: Then, for Santa’s Village, Chris Columbus and Jon Hutman, the production designer, wanted to build as much of the village as possible. The key for me was to get a three-plus wall set all the way around so you have about 300 degrees of full set. It came up to more or less two stories height, slightly less in some places, but we could then extend that up. The idea there was we could get as much practically in camera if we were shooting just drama shots of Kurt and Goldie and the elves—fortunately the camera was always looking down for them. Whenever there was a wide or whenever there’s a high move, then there’s a massive set extension. We based all that on Swiss and Austrian villages.

Phil Leonhardt: There are some lovely places in the European Alps, particularly Switzerland and Austria that are larger villages that sit within those mountain ranges and valleys that are great reference for how you would lay out and populate these sort of environments. We also looked at the vegetation; where does the forest take over, and how are the houses scattered up the hill?

Jola the Yule Cat

Martin Hill: He’s a massive cat. He started at the size of about a lion and then just went bigger and bigger from there. It was basically, ‘Well, we’re up to polar bear size now. How is this going to run and still look feline?’

Phil Leonhardt: The bigger the cat, essentially the more detail in the fur you need because you can’t just scale up your fur sims and your fur detail with the size of the actual puppet. So there was a little bit of development and design that needed to go into it in order to make that believable so when he stands right next to Belsnickel or has a little elf on the back of his shoulders, he doesn’t look like he’s not fitting into the same world.

Belsnickel’s Jack-a-lotes and the sleigh chase

Nick Stein: The Jack-a-lotes went through quite a design phase. We had them looking quite differently earlier on. They were split between a hybrid of jackals and coyotes. There was a little bit of hyena in there, too. We looked at every kind of creature we could look at and picked pieces that really worked. They had that slightly elongated neck—the hyena kind of look—and the kind of run that they do also helped.

These guys are also running through the air, so then we also how to look at, how do their feet work? They’re not actually planting on a ground. So are they more swoopy or swingy? We really wanted each one to have its own personality, so you can see the grumpy one in the background that doesn’t really want to be there, and the manic one that loves to lick the guy beside him, and the angrier one that bites at the reindeer.

Martin Hill: All of Belsnickel’s tech is very cobbled together and made of broken bits and pieces. So we knew these Jack-a-lotes just had to be crazy. Chris Columbus has a French bulldog, who would be barking away in the back of calls with him that we had, and it was like, ‘Oh, can you put a little bit of French bulldog in there?’ With the design, we were talking to the art directors here at Weta. It was like, ‘Let’s make sure we can make the eyes really bulge and give them a tongue that’s long enough to slap them in the eye. Don’t know how we’re going to use it yet, but we’re definitely going to use it.’

Martin Hill: For one of these aerial sleigh scenes, originally the script said, ‘Santa’s chasing Jola Cat through the wilderness to the sounds of Led Zeppelin’s Immigrant Song. I was like, ‘Fantastic!’ So in previs, we timed everything to the music. Jola enters frame just as the guitars come in. Santa comes in right on Robert Plant’s vocals. We shot all the sleigh gimbal stuff, which was planned with techvis, based on that. The music wasn’t actually used in the final film, but you can overlay it and it still works exactly.

We planned this big, long chase. It was actually a lot longer in the original previs. We had this whole piece based around Ben-Hur, and actually we had a coliseum scene in there, hence the blades that come out of Belsnickel’s sleigh. We previs’d the whole wormhole setup and then techvis’d what the gimbal rig needed to do for both sleighs. We had six-axis hydraulic sleighs for both sleighs running at the same time, both on track rollers. It was a quite sophisticated setup with a Technocrane camera, so you’re inverting a lot of the sleigh motion back into the camera, which means you need to adjust the lighting as you go. And just having all that planned and being flexible enough on the stage was vital. That was all shot on a bluescreen stage in Vancouver.

Thrain Shadbolt: It’s worth noting that we had complete CG models of both sleighs as well to clean up the rig that the practical sleighs were mounted on, but also to get the interactive lighting and some of the effects happening. And then of course beyond that, it’s on bluescreen, so we had to create the whole environment as well.

Martin Hill: At some point, too, we were watching lots of snowboarding and skiing reference. And a lot of that stuff is shot on Go-Pros, people holding Go-Pro cameras to themselves. I thought, ‘Oh, it’d be a terrific idea if we took a Go-Pro and attached it to one of the reindeer’s horns and just have a closeup of what the reindeer are going through—on their eye—super wide angle.’ We had this perfect moment where the reindeer are looking really scared. How do we show that they’re scared but aren’t completely losing plot? So we had this big close up of Comet’s eye just getting really wide and terrified.